[PATCH 3.10 005/103] irqchip: Gic: Support forced affinity setting

[mark.rutland@arm.com (Mark Rutland)]

On Thu, Jun 05, 2014 at 07:05:24PM +0100, Greg Kroah-Hartman wrote:
> On Thu, Jun 05, 2014 at 05:05:00PM +0100, Mark Rutland wrote:
> > Hi Greg,
> > 
> > On Thu, Jun 05, 2014 at 12:24:28AM +0100, Greg Kroah-Hartman wrote:
> > > 3.10-stable review patch.  If anyone has any objections, please let me know.
> > > 
> > > ------------------
> > > 
> > > From: Thomas Gleixner <tglx@linutronix.de>
> > > 
> > > commit ffde1de64012c406dfdda8690918248b472f24e4 upstream.
> > > 
> > > To support the affinity setting of per cpu timers in the early startup
> > > of a not yet online cpu, implement the force logic, which disables the
> > > cpu online check.
> > > 
> > > Tagged for stable to allow a simple fix of the affected SoC clock
> > > event drivers.
> > 
> > This patch alone has the possiblity of breaking CPU hotplug on arm and
> > arm64 (specifically it breaks hot unplugging CPU0 where interrupts may
> > be left targetting the offline CPU).
> > 
> > For arm64 [1] that's fixed by commit 601c942176d8 (arm64: use
> > cpu_online_mask when using forced irq_set_affinity).
> 
> Thanks, I'll apply that to the 3.14-stable tree, but, it doesn't seem
> relevant at all for 3.10-stable as arch/arm64/kernel/irq.c doesn't do
> anything with cpumask or set_affinity.  If it's relevant for 3.10,
> please provide a backported version.

Sorry, my bad. It's not relevant for v3.10, I'd gotten confused over
when I added CPU hotplug.

Thanks,
Mark.

> > Unfortunately there is not an equivalent fix for arm - Russell objected
> > to the approach [2,3,4], and that's not yet settled.
> 
> Ok, be sure to cc: stable on the patch when it goes into the tree and
> I'll pick it up then.
> 
> thanks,
> 
> greg k-h
>